Hi. You can bring your parents within one week also. Follow the below mentioned link for one month visit visa to Qatar at QR 100 which is a facility provided by Govt and applicable for all age groups including senior citizens.
Note: this visa facility is available during the period of asian cup only so hurry up... & apply on line.

http://portal.www.gov.qa/wps/portal/services/asiancupvisa/?changeLanguag...